Vacuum tube (Fleming diode, De Forest triode)
Válvula de vacío (diodo de Fleming, triodo de De Forest)
- Date
- 1904–1906 · confidence high
- Place
- London, England
- Credited to
- John Ambrose Fleming (diode, University College London, 1904); Lee De Forest (Audion/triode, New York, 1906); Robert von Lieben (Vienna, 1906)
- People
- 👤 John Ambrose Fleming1849–1945👤 Lee De Forest1873–1961👤 Robert von Lieben1878–1913
- Field
- Matter & energy
⚠️ Disputed: the sources disagree.
What it is
The diode rectifies radio signals; the triode, by adding a grid, amplifies and oscillates. It was the first active electronic component and the basis of all electronics until the transistor.
De Forest did not understand how the triode worked; Edwin Armstrong and Irving Langmuir explained and perfected it (high vacuum, 1913). Von Lieben independently patented an amplifying tube.
What it led to
- Voice radio and broadcasting
- Transcontinental telephony (1915) and amplifiers
- Electronic computers (Colossus, ENIAC)
Built on
Made possible
- Condenser microphone1916
- Sonar (ASDIC)1915–1918
- Radio broadcasting1906–1920
- Moving-coil loudspeaker1924–1925
- Electronic television1927–1936
- Sound film1926–1927
- Electroencephalogram (EEG)1924–1929
- Cyclotron1930–1932
- Magic eye tube1932
- Radar1935
- Magnetic tape recording (Magnetophon)1928–1935
- Colossus computer1943–1944
- ENIAC1945